title: Effects of potassium on expression of renal sodium transporters in salt-sensitive hypertensive rats induced by uninephrectomy.
abstract: Dietary potassium is an important modulator of systemic blood pressure (BP). The purpose of this study was to determine whether dietary potassium is associated with an altered abundance of major renal sodium transporters that may contribute to the modulation of systemic BP. A unilateral nephrectomy (uNx) was performed in male Sprague-Dawley rats, and the rats were fed a normal-salt diet (0.3% NaCl) for 4 wk. Thereafter, the rats were fed a high-salt (HS) diet (3% NaCl) for the entire experimental period. The potassium-repleted (HS+KCl) group was given a mixed solution of 1% KCl as a substitute for drinking water. We examined the changes in the abundance of major renal sodium transporters and the expression of mRNA of With-No-Lysine (WNK) kinases sequentially at 1 and 3 wk. The systolic BP of the HS+KCl group was decreased compared with the HS group (140.3 ± 2.97 vs. 150.9 ± 4.04 mmHg at 1 wk; 180.3 ± 1.76 vs. 207.7 ± 6.21 mmHg at 3 wk). The protein abundances of type 3 Na(+)/H(+) exchanger (NHE3) and Na(+)-Cl(-) cotransporter (NCC) in the HS+KCl group were significantly decreased (53 and 45% of the HS group at 1 wk, respectively; 19 and 8% of HS group at 3 wk). WNK4 mRNA expression was significantly increased in the HS+KCl group (1.4-fold of control at 1 wk and 1.9-fold of control at 3 wk). The downregulation of NHE3 and NCC may contribute to the BP-attenuating effect of dietary potassium associated with increased urinary sodium excretion.
authors.affiliation: Department of Internal Medicine, Gachon University of Medicine and Science, Incheon, Korea.
authors.forename: Ji Yong
authors.initials: JY
authors.lastname: Jung
authors.forename: Sejoong
authors.initials: S
authors.lastname: Kim
authors.forename: Jay Wook
authors.initials: JW
authors.lastname: Lee
authors.forename: Eun Sook
authors.initials: ES
authors.lastname: Jung
authors.forename: Nam Ju
authors.initials: NJ
authors.lastname: Heo
authors.forename: Min-Jeong
authors.initials: MJ
authors.lastname: Son
authors.forename: Yun Kyu
authors.initials: YK
authors.lastname: Oh
authors.forename: Ki Young
authors.initials: KY
authors.lastname: Na
authors.forename: Jin Suk
authors.initials: JS
authors.lastname: Han
authors.forename: Kwon Wook
authors.initials: KW
authors.lastname: Joo
mesh_terms: D000818:Animals; D006973:Hypertension / Q000378:metabolism* / Q000503:physiopathology; D007668:Kidney / Q000187:drug effects / Q000378:metabolism* / Q000503:physiopathology; D008297:Male; D009392:Nephrectomy / Q000379:methods*; D017419:Potassium, Dietary / Q000378:metabolism* / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D049992:Sodium Chloride Symporters / Q000378:metabolism*; D017673:Sodium Chloride, Dietary / Q000378:metabolism / Q000494:pharmacology; D028021:Sodium-Potassium-Chloride Symporters / Q000378:metabolism*; D018709:Statistics, Nonparametric
chemical_list: D017419:Potassium, Dietary; D049992:Sodium Chloride Symporters; D017673:Sodium Chloride, Dietary; D028021:Sodium-Potassium-Chloride Symporters